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Plant MaterialTylophora indica leaves were collected from herbal garden, Jamia Hamdard and authenticated by the taxonomist of Department of Botany, Faculty of Science, Hamdard University. The voucher specimen was deposited in the herbarium of university for future reference.The methanolic extract of Tylophora indica leaves was screened for hepatoprotective activity in carbon tetrachloride induced hepatotoxicity in albino rats. The degree of protection was measured by estimating biochemical parameters like Serum glutamate oxaloacetate transaminase, serum glutamate pyruvate transaminase, total protein and level of serum bilirubin (both total and direct). Hepatoprotective activity of methanolic extract at a dose of 200 mg/kg and 300 mg/kg body weight, i.p., was compared with Silymarin (25 mg/kg, i.p.) treated animals. Tylophora indica leaves (200 and 300 mg/kg) exhibited significant reduction in serum hepatic enzymes when compared to rats treated with carbon tetrachloride alone. Furthermore, histopathological studies were also done to support the study.

<p><strong>Objective: </strong><a href="http://www.webmd.com/diabetes/default.htm">Diabetes</a> mellitus is a chronic metabolic disease which affects our body's ability to use the energy found in food. Our study was planned to isolate chemical constituents from the leaves of <em>Psidium guajava</em> L. (Myrtaceae), to characterize their structures and to investigate their antidiabetic activity.</p><p><strong>Methods: </strong>The air-dried leaf powder was exhaustively extracted with methanol in a Soxhlet apparatus. The concentrated leaf extact was adsorbed on silica gel (60-120 mesh) for the preparation of a slurry. The dried slurry was chromatographed over silica gel column packed in petroleum ether. The column was eluted with petroleum ether, chloroform and methanol, successively, in order of increasing polarity to isolate the compounds. These natural constituents were tested for the antidiabetic activity in STZ-induced diabetic models.</p><p><strong>Results: </strong>Six new lanosterol-type triterpenoids characterized as lanost-7-en-3β-ol-26-oic acid (2), lanost-7-en-3β, 12β-diol-26-oic acid (3), lanost-7-en-3β, 12β, 29-triol-26-oic acid (4), lanost-cis-1,7,23-trien-3β, 12β, 18, 22α-tetraol-26-oic acid (5), lanosteryl-3β-O-D-xylopyranosyl-2′-<em>p</em>-benzaldehyde (7) and lanost-7-en-3β-ol-26-oic acid-3β-D-glucopyranoside (8) along with the known compounds arachidic acid (1) and β-sitosterol xylopyranoside (6) were isolated from the leaves. The compounds 2, 3, 4 and 8 exhibited significant antidiabetic activity against streptozotocin-induced diabetic rats.</p><p><strong>Conclusion: </strong>The leaves of <em>P. guajava </em>possessed antidiabetic lanostene-type triterpenoids<em>.</em></p>

Punica granatum Linn. (Punicaceae) is a large deciduous shrub or small tree, up to 10 m in height, that grows well in the warm valleys and hills of the Himalayas and is cultivated throughout India [1]. In traditional Ayurvedic medicine, all parts of P. granatum are used for the treatment of various disorders [2]. The flowers of P. granatum are used in folk medicine for the treatment of bronchitis, diarrhea, dysentery, ulcers, hepatic damage, sore eyes, and diabetes [3,4]. Phytochemical investigation of P. granatum flowers showed the presence of various phenolic compounds, pentacyclic triterpenes, and sterols [5, 6]. The present paper describes the isolation and characterization of two new flavonoids (1, 2) from the flowers of P. granatum along with the known compounds ellagic acid (3), gallic acid (4), sucrose (5), and gallic acid glucoside (6).Compound 1, named punicaflavanol, was obtained as pale yellow crystals from chloroform-methanol (19:1) eluats. It responded positively to the tests of flavonoids. The UV spectrum of 1 displayed absorption maxima at 281 and 363 nm, indicating the flavanol type nature of the molecule. It showed shift of bands with sodium methoxide, suggesting presence of the free hydroxyl groups in the molecule. The shift of band II to 316 nm on addition of sodium acetate suggested the presence of the 7-hydroxyl group with the 5-hydroxyl group. The shift of band II to 293 nm on addition of sodium acetate and boric acid indicated the location of A-ring o-dihydroxyl groups. The appearance of band II at 301 nm on addition of AlCl 3 indicated the existence of the 5-hydroxyl group in the flavanone. The shift of band II to 293 nm on addition of AlCl 3 +HCl supported the A-ring o-dihydroxy groups [7-9]. Its IR spectrum displayed the characteristic absorption bands for the hydroxyl groups (3561, 3509, 3136 cm -1 ) and the carbonyl group (1696 cm -1 ). The mass spectrum of 1 exhibited a molecular ion peak at m/z 366, pointing to the molecular formula C 16 H 14 O 10 . The retro-Diels-Alder fragmentation of ring C yielded the diagnostic peaks at m/z 184 and 182, supporting the presence of four hydroxyl groups in ring A and three hydroxyl and one methoxyl groups in ring B, respectively.